The present invention relates to a carton handling machine, and more particularly, to an improved machine for erecting initially folded cartons.
In the past, a variety of packaging machines have been designed, including those disclosed in U.S. Pat. No. 3,107,013 titled "Method and Means For Stacking Articles"; No. 3,134,309 titled "Apparatus for Erecting Packing Cases"; No. 3,236,027 titled "Packaging Machine"; No. 3,299,611 titled "Packaging Machine"; No. 3,323,283 titled "Apparatus for Handling Cases Being Loaded"; No. 3,343,335 titled "Apparatus for Setting-up and Filling Cartons"; No. 3,584,434 titled "Carton Handling and Loading Method and Apparatus Machine"; and No. 3,954,165 titled "Automatic Collating Machine".
In these patents, a number of mechanisms for handling and erecting folded cartons are disclosed. U.S. Pat. No. 3,134,309 discloses a mechanism which includes rotatable suction cups which lift the trailing top wall of a carton as it passes by. In U.S. Pat. No. 3,299,611, a mechanism is disclosed wherein pneumatically actuated, vertically directed "pre-break fingers" raise a carton slightly, and conveyor fingers complete the erection. U.S. Pat. Nos. 3,323,283 and 3,343,335 disclose more mechanisms which include suction cups; in U.S. Pat. No. 3,323,283, the suction cups are both above and below the passing cartons, while in U.S. Pat. No. 3,343,335, the suction cups pull cartons down to a conveyor belt from an overhead bin. Finally, a pneumatically actuated, vertically directed plunger is disclosed in U.S. Pat. No. 3,584,434, which extends through an opening in the lower wall of a folded carton to push the upper walls upward.
While the mechanisms disclosed in the identified patents have been useful in the past, each has certain limitations and disadvantages. For example, the mechanism of U.S. Pat. No. 3,584,434 is useful with only cartons having holes through which the plunger may extend. Further, U.S. Pat. Nos. 3,134,309, 3,323,283 and 3,299,611 all involve suction cups, and thus may be limited to use with cartons of a material to which suction cups can effectively attach. Also, a substantial amount of energy is expended in supplying a vacuum to suction cups. The purpose of the present invention is to overcome these and other disadvantages and limitations of prior devices.